Cardiovascular Disease Articles

By Jon-Emile S. Kenny [@heart_lung] When interpreting hemodynamic studies of drugs which – potentially – alter the resistance of the pulmonary vascular tree, we often turn to the calculated pulmonary vascular resistance [cPVR] as our guide. For instance, a vasopressor determined to increase the cPVR is wholly avoided in a patient with pulmonary arterial hypertension. We [… read more]

What’s the shelf life of human blood? Like the milk in your fridge, stored donated human blood has an expiration date: currently it’s 42 days, set by the FDA. But is fresher blood actually better? As with ordering wine by the glass, should patients about to be transfused blood ask for “whatever was opened most recently”? There’s [… read more]

“Major Major had been born too late and too mediocre. Some men are born mediocre, some men achieve mediocrity, and some men have mediocrity thrust upon them. With Major Major it had been all three …” -Joseph Heller In my younger days, parked on a bench overlooking Stanley Park, I sought truth in the absurdist [… read more]

“I want to be your medicine, I want to feed the sparrow in your heart …” -Kristian Matsson Case A 39 year old woman is admitted to the intensive care unit for hypotension, anuria and altered mentation despite 3 litres of intravenous lactated ringers infusion. She is febrile and found to have gram negative bacteremia [… read more]

The Rise of Mechanical Circulatory Support Devices What Critical Care Physicians Need to Know Felipe Teran-Merino M.D. Part 2 of 2 (read part 1) II. Main MCS devices used for emergency and short-term support Intra-Aortic Balloon Pump The oldest and simplest mechanical device is the intra-aortic balloon pump (IABP). Introduced in 1968, the IABP is still used as a [… read more]

The Rise of Mechanical Circulatory Support Devices What Critical Care Physicians Need to Know Felipe Teran-Merino M.D. Part 1 of 2 (read part 2) I. The failing pump and hemodynamic rationale for the use of MCS devices The rising field of mechanical circulatory support (MCS) offers a spectrum of therapies and devices with the potential to rescue patients [… read more]

A 23 year old woman is admitted with severe abdominal pain following 5 days of profound non-bloody diarrhea and 72 hours of recalcitrant non-bloody emesis. She has lost 7 pounds in this time frame and has been unable to maintain oral hydration. Her eyes are sunken and her vital signs are notable for a heart [… read more]

A 58 year old man with ethanol-related cirrhosis is admitted to the floor with anuria and a rising creatinine. Over the day, serial ultrasounds of his interior vena cava [IVC] consistently reveal that it is diminutive and collapsing. He receives many liters of crystalloid without much change in his urine output. In the middle of [… read more]

New oral anticoagulants like dabigatran, apixaban and rivaroxaban have advantages over warfarin: not requiring regular monitoring for efficacy; faster onset of action; shorter half-lives. Unlike warfarin, they’ve had the significant disadvantage of having no proven antidote for the bleeding that inevitably occurs when any anticoagulant is given to thousands of people. [lawsuits] Boehringer Ingelheim, makers [… read more]

Not long ago, doctors were taught that 6 months of anticoagulation was plenty for patients with unprovoked pulmonary embolism. That standard was never based on long-term outcomes studies. And as longer-range data started to come in — gulp — it was clear that large numbers of people treated with 6-month warfarin courses after unprovoked PE [… read more]

Direct thrombin inhibitors (DTIs) are anticoagulants (blood thinners) most often used as alternatives to heparin and warfarin. DTIs are approved by the FDA for prevention and treatment of venous thromboembolism (deep venous thrombosis and pulmonary embolism) and to prevent blood clots in people with atrial fibrillation. But multiple randomized trials suggest these widely used anticoagulants might cause heart [… read more]

Endovascular Therapy Improves Outcomes from Ischemic Stroke By Parth Rali, MD and Igor Titoff, DO Endovascular therapy for ischemic stroke has long been an attractive treatment modality for ischemic strokes, but until recently large randomized trials have not confirmed a benefit [1,2,3]. Two of these—IMS III1 and SYNTHESIS2—failed to prove the benefit of endovascular therapy (with-or-without tissue plasminogen activator) [… read more]

ICU Physiology in 1000 Words The Right Ventricular Afterload [Part 2 of 2] Jon-Emile S. Kenny M.D. [@heart_lung] Having considered the short-comings of Laplace’s Law and the PVR with respect to the RV afterload in part 1, we will now turn to each of the following in turn: the pulmonary arterial input impedance, a measureable [… read more]

Cardiopulmonary Resuscitation by Jon-Emile S. Kenny, MD The first time I performed cardiopulmonary resuscitation [CPR] on a patient was in the emergency department of Sunnybrook Hospital in Toronto, Canada; it was certainly an indelible moment in my training. As an intern, and especially as medical consult at Bellevue Hospital in New York City, I was [… read more]

Stroke Volume Variation and the Concept of Dose-Response Jon-Emile S. Kenny M.D. Awareness of the undulating pattern of an arterial line tracing is high amongst health professionals in the intensive care unit; certainly this is an aftereffect of a cacophony of studies and reviews pertaining to pulse pressure variation and fluid responsiveness in the operating [… read more]

The American College of Chest Physicians (unaffiliated with PulmCCM) published its new consensus guidelines in August 2014 for the drug treatment of pulmonary arterial hypertension (PAH). They’re free to view on the Chest website, and well worth a look. Remember that pulmonary arterial hypertension (PAH) is but one small subset (“Group 1”) of the much larger [… read more]

About half of people diagnosed with obstructive sleep apnea (OSA) can’t or won’t use the most effective therapy, overnight continuous positive airway pressure (CPAP). Most people with untreated OSA experience multiple episodes of hypoxemia — sometimes hundreds per night. For many patients declining CPAP treatment, their doctors provide overnight oxygen, in the hope that it might [… read more]

Image: EKOS Patients with acute pulmonary embolism (PE) fall into three general clinical categories: Massive PE, most often defined as hypotension due to right ventricular dysfunction. Short-term mortality is high (more than 1 in 7 die in-hospital). Systemic thrombolytic therapy (tissue plasminogen activator or tPA) is considered standard care by AHA and ACCP, because it [… read more]

Beta-Blockers: Safe (and Effective?) for Most Patients with Asthma, COPD Once upon a time in 1964, it was noted that propranolol, a nonselective beta-blocker, could precipitate severe bronchospasm in patients with asthma, especially at high doses. Additional small studies showed propranolol and other nonselective beta blockers could increase airway resistance. British guidelines advise avoiding beta [… read more]